Sniffly Surfing: Google Unveils Flu-Bug Tracker

• NOVEMBER 12, 2008

Sniffly Surfing: Google Unveils Flu-Bug Tracker

By ROBERT A. GUTH

http://online.wsj.com/article/SB122644309498518615.html

You can Google to get a hotel, find a flight and buy a book. Now you may be able to use Google to avoid the flu.

One month into flu season, Google Inc. on Tuesday opened a free Web service that the Internet company says can show if the number of influenza cases is increasing in areas around the U.S., earlier than many existing methods.

A screen shot from Google's Flu Trends site.

The service, called Flu Trends (www.google.org/flutrends), uses computers to crunch millions of Internet searches people make for keywords that might be related to the flu -- for instance "cough," or "fever." It displays the results on a map of the U.S. and shows a chart of changes in flu activity around the country. The data is meaningful because the Google arm that created Flu Trends found a strong correlation between the number of Internet searches related to the flu and the number of people reporting flu symptoms.

Google built the service with the guidance of the Centers for Disease Control and Prevention, the U.S. government's public-health watchdog that runs a range of flu-surveillance systems. Flu Trends can be a complement to those tools, health officials say.

Flu Trends "maps very closely to the influenza-like trends that we see in the U.S.," says Lyn Finelli, lead of the influenza surveillance team at CDC's headquarters in Atlanta.

The service adds Google to a growing number of Web sites that are trolling, culling and crunching Internet data in ways to better pinpoint and predict where diseases are hitting around the world. The sites use varying degrees of human and computer methods for detecting outbreaks and many have historically been aimed at doctors and health-care professionals. Google executives say their service could also appeal to consumers.

In any given year, between 5% and 20% of Americans can catch the flu, depending upon the strength of a particular flu virus and other factors, the CDC says. Around 145 million doses of flu vaccines will be available this flu season, which generally runs from October to May and typically peaks in February.

Finding a new tool to stave off infection is important to Maureen Rinehart, a 28-year-old kindergarten teacher in San Francisco. Ms. Rinehart says daily contact with her kids means she gets sick about once a month. She got a flu shot about two weeks ago and is armed with hand sanitizer in the classroom.

"They're really snotty and they want to hold hands with you; you know how it is with the little guys," says Ms. Rinehart. So if the Google service shows flu cases are rising, she says, "you could bulk up on vitamins and wash your hands more -- all the necessary things you should do."

The Google service is the brainchild of Google.org, a three-year-old group at the Mountain View, Calif., company that works on areas for the public good -- such as renewable energy -- that may or may not have a direct financial benefit to Google. The company won't use advertising on the Flu Trends site.

The Google group examined flu-related keywords over five years, noting times when searches of those terms surged. It then compared those times to CDC records and found a strong correlation between when people searched flu keywords and when people have had flu-like symptoms. It spent the past year testing new search results against data from the CDC, tweaking its software to make its results more accurate, Google executives said.

The Flu Trends site displays results of its analysis in a five-tier scale of flu activity ranging from "minimal" to "intense," with a middle point of "moderate." The site includes CDC flu prevention messages, a flu vaccination locator and links to flu-related news items.

"It's still quite experimental," says Jeremy Ginsberg, Google's lead engineer on Flu Trends. "We feel it's an interesting, unique way to track disease outbreaks."

In 2003, the Canadian government and other organizations used versions of these data-collection and health sites to detect early signs of the SARS virus in China. The Canadian service -- the Global Public Health Intelligence Network -- automatically scans Web sites and news sources in seven languages for information on disease outbreaks, contaminated food and water, natural disasters and other health risks around the world. It charges a fee based on the type of organization that accesses it and its usage.

At Harvard Medical School's Children's Hospital Boston, a site called HealthMap crawls through 24,000 Web sites looking for disease-related terms. Results appear on a world map, which has colored markers for dengue fever, avian flu and other diseases.

Google.org last month started funding HealthMap to find ways to collaborate with ProMED, a site that uses people to gather clues about diseases from the Web and from other sources.

The Web-based services have shortcomings. The most accurate way to measure a disease outbreak is by the number of actual cases confirmed by a laboratory. By tracking keywords in news stories and search results, the Web sites can't guarantee that they are finding actual outbreaks.

But what they lose in accuracy, the sites may make up in speed. Getting accurate data on real disease cases requires people to be tested for a disease and that data to be collected by public-health organizations. While the CDC and other organizations do this kind of research, it takes time.

Reducing that time is crucial for combating influenza, which can manifest itself one to three days after a person comes into contact with the virus. "If you get data that's not very timely one or two weeks old it's possible that the outbreak has already peaked," the CDC's Ms. Finelli says.

Still, some consumers question how helpful the new Google health service will be for them. Tony Deen, a 22-year-old recent college grad in San Francisco, says he hasn't had the flu since he was a kid and uses health Web sites only when he has a medical problem. "It's not like I can flee the city if the flu is coming," Mr. Deen says. But "it might convince me to get a flu shot if people are getting sick."

Write to Robert A. Guth at rob.guth@wsj.com